Apparatus for the size reduction of refuse



Dec. 14, 1965 F. WUTHRICH APPARATUS FOR THE SIZE REDUCTION OF REFUSE 2 Sheets-Sheet 1 Filed June 26, 1963 Dec. 14, 1965 wU c 3,223,334

APPARATUS FOR THE SIZE REDUCTION OF REFUSE Filed June 26, 1963 2 Sheets-Sheet 2 INVENTOR 5/22 Mum-:1

United States Patent 3,223,334 APPARATUS FOR THE SIZE REDUCTISN 0F REFUSE Fritz Wiithrich, Zollikerberg, Switzerland, assignor to Von Roll A.G., Gerlafingen, Switzerland, a corporation of Switzerland Filed June 26, 1963, Ser. No. 299,792

Claims priority, application Switzerland, July 2, 1962,

7,878/ 62 16 Claims. (Cl. 24136) The present invention generally relates to an improved apparatus for the size reduction of refuse, particularly refuse which is to be destroyed by combustion.

The process most frequently employed for the disposal of refuse which, as is known, accumulates in very large quantities, is the incineration or combustion of such refuse. However, it is a characteristic of refuse that it is not only very inhomogeneous as regards the type thereof, but also is very inhomogeneous in size.

In such refuse, in addition to there being present bulk or loose material and small goods or material, there is also present parceled goods or pieces of material, which in certain instances can be considerably bulky, as for eX- ample is the case with boxes or parts thereof, packaging crates, old furniture pieces and so forth. In order, however, to provide good combustion conditions for such goods in the refuse incineration plant there is required to be deposited upon the combustion grate a layer of combustible material which is as homogeneous and also uniformly thick as i possible. However, with the aforementioned type of bulky and different sort of constituents of the combustible material, such a condition of the combustible material cannot be achieved without providing specific measures.

In order to obtain good charging and, therewith, a rational combustion of the refuse upon the grates of such refuse incineration plants, devices are already known to the art which are arranged before the refuse incinerator and which reduce in size the accumulated refuse by mechanical processing thereof. To this end, mixing drums are known which are inclined to a lesser or greater extent and provided with or without fittings or installations, in which the combustion material is not only thoroughly mixed, but is also reduced in size. However, such apparatus have the disadvantage, apart from their limited size reduction capability, that they cannot be accommodated to the properties or condition of the refuse, so that they readily tend to clog or the refuse arches or forms bridges, whereupon their already limited effectiveness is still further strongly impaired. Consequently, it is thus oftentimes necessary to resort to manual sorting in order to eliminate such bulky objects from the accumulated refuse and, then, to individually reduce in size such objects. The expenditure of manual labor for this purpose is not only expensive but also undesirable for hygienic reasons.

The present invention therefore has as one of its primary aims to provide an improved apparatus for the size reduction of refuse in which such aforementioned disadvantages are overcome and, above all, to ensure for the necessary adaptation or accommodation of the apparatus to the properties of the refuse to be burned.

Broadly speaking, the apparatus of the present invention is characterized by the fact that there is provided two frame members, at least one of which is rotatably or pivotably mounted at one end, and further by drive means for pivoting the rotatably mounted frame towards the other frame. Both such frames are advantageously provided with shearing rods or means at least at the portions thereof bounding the pivot axis, with the shearing 3,223,334 Patented Dec. 14, 1965 means of any one frame being offset with respect to the shearing means of the other frame in such a manner that, the aforesaid shearing means of both frames intermesh or interengage with one another in comb-like fashion in the one extreme position of the pivotable frame.

Thus, a further important object of the present invention is to provide an improved apparatus for the size reduction of refuse or the like preparatory to its destruction, particularly for destruction thereof by combustion, manifested by the features that such apparatus is efficient and extremely reliable in operation, will not readily become clogged, and can be easily and quickly accommodated to the properties of the refuse being handled.

Another important object of this invention is to provide an improved apparatus for reducing in size refuse which is to be destroyed, comprising a pair of frame members, at least one of which is pivotable towards the other, drive means for each such pivotable frame member, with said frame members being provided with interfitting shearing means.

Yet a further object of this invention is to provide improved apparatus for the size reduction of refuse comprising frame means mounted for relative pivotal movement away from and towards one another, into an opening and closing position, respectively, drive means for said frame means, and control means for said drive means presettable to a specific maximum closing force for limiting the closure stroke of the pivotable frame or frames, whereby such pivotal frame or frames upon reaching a position corresponding to the maximum preset closure. force is automatically returned into its or their open position, due to action of the control mean upon the drive means, so that the refuse can successively slide down hetween the frame means from one opening stroke thereof to the other, and under the influence of an effectively increasing compression force such refuse is first crushed and/or compressed, depending upon the properties of the refuse, and finally is reduced in size by means of cooperating shearing means provided for said frame means.

These and still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of i1- lustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

In the drawings:

FIGURE 1 schematically illustrates a side-view of the apparatus for the size reduction of refuse designed according to the teachings of the present invention;

FIGURE 2 illustrates details, in plan view, of a portion of the apparatus shown in FIGURE 1; and

FIGURE 3 schematically depicts details of a control system for the refuse size reduction apparatus depicted in FIGURES 1 and 2.

Referring now to the drawings, in FIGURE 1 there is depicted a frame member 1 which is stationarily arranged internally of a suitable housing open at its upper and lower end (not shown). In the illustrated embodiment, a second frame member 2 is pivotably connected through the agency of a link or hinge connection 3 with the lower end of the stationary frame 1, so that the aforesaid frame 2 can be pivoted or rocked towards and away from the frame 1. A hydraulic or pneumatic cylinder 4, which for example is operated by a pressurized oil medium, rests at its lower end upon a rigid support 5 and is connected to said support via a hinge member 6. In the cylinder 4 there is slidably arranged a working piston 7 having a piston rod 8 which extends piercingly through a packing box 9 of this cylinder 4 and is connected through the agency of a hinge member 10 to pivotable frame 2, as shown. The cylinder 4 is constructed to be double-acting and is operatively connected to a pump assembly or unit 14, consisting of an electric motor 14a and a suitable pump 1412, via two supply lines or conduits 11 and 12 and through the agency of a control device or means 13, to be described in greater detail shortly with reference to FIGURE 3. The fluid pressure selectively transmitted through the supply lines 11 and 12 and acting against the lower and upper face, respectively, of the working piston 7 is adjustable at this control device 13.

Both of the frames 1 and 2 are equipped at their lower portions with spaced shearing rods or elements defining shearing means 15 and 15', respectively, which extend approximately vertical to the pivot axis 3' of the hinge connection 3, as such is best seen for example in FIGURE 2, depicting in plan view the lower region of the pivotable frame 2. These sheaving means 15, 15, shown by way of illustration as formed of spaced strip members, are profiled in such a manner, and offset with respect to one another from frame to frame that, when the frame 2 is rocked towards the stationary frame 1, that is to say, into its closing position depicted in phantom lines in FIGURE 2, the shearing means of the one frame, such as frame 2, always engages or interfits in a comb-like manner with the window-shaped spaces or recesses 15a formed by the shearing means of the other frame 1. As will be seen from FIGURE 1 the recesses 15a extend completely throughout the thickness of the corresponding frame members 1 and 2, so that the spaced strips of shearing means 15' of frame member 2 can completely pass through the recesses 15a of the shearing means 15 of frame member 1.

A resilient or spring-biased shutter or cover member 16 is arranged at the external side of the stationary frame 1 and is secured at a location 16a to the frame 1. This cover 16 closes the frame 1 which bears against said cover towards its lower end when the pivotable frame 2 is situated in its original or starting pivoting position, that is, in the open position thereof. The resilient mounted cover or shutter 16 is adapted to be raised from the frame 1 first, and only then, when the shearing means 15 of the pivotable frame 2 which is advantageously arched in convex manner in the direction of closing, extends through the recesses 15a of the stationary frame 1, which occurs shortly before the frame 2 has reached its most extreme closing position; and finally, with further pivoting of the frame 2 into its end closing position takes along the shutter 16 against its spring force. This open position of the shutter 16 is shown in phantom lines in FIGURE 1, with the shearing means 15 of the frame 2 extending through the shearing means 15 of the frame 1.

Referring now to FIGURE 3, it will be seen that there is schematically depicted therein, by way of example and not limitation, a possible arrangement of the control means 13 for adjusting and controlling the infeed of the pressurized fluid medium, such as oil, from the pump 14b to the lower and upper face, respectively, of the piston member 7 slidably disposed in the cylinder 4. Thus, the control means 13 advantageously comprises a slide valve cylinder 30 internally provided with a slide valve piston 31 including the spaced piston lands 32 and 33. The interior of the slide valve cylinder 30 communicates with the high-pressure side of the pump 14b driven by motor 14a via a pressure line 34. Depending upon the position of the slide valve piston 31 within its slide valve cylinder 39 such pressurized medium will be admitted to the bottom face of the piston 7 within cylinder 4 via line 11 or to the top face of such piston 7 via line 12. Thus, for example, if the slide valve piston 31 assumes the position shown in full lines in FIGURE 3, then the pressurized medium moves from the infeed line 34 into the space between the piston lands 32, 33 and then to conduit or line 11 to the bottom face of the piston 7 to force such piston upwardly toward the top end of the cylinder 4, with any fluid medium contained above the upper face of such piston 7 being expelled through line 12 into the slide valve cylinder 30 and through lines 35 and 36 back to the lowpressure side of the pump 14b. On the other hand, if the slide valve piston 31 assumes the position shown in dotted or phantom lines in FIGURE 3, then the pressurized fluid medium is supplied to the upper face of the piston 7 via the infeed line 34 and pressure line 12, with the fluid appearing beneath the lower face of this piston 7 being returned to the low-pressure side of the pump via lines or conduits 11, 37 and as. It should thus be appreciated that, depending upon the position of the slide valve piston 31 wthin its slide valve cylinder 30, the pressurized fluid medium is admitted to the one or the other end of the cylinder 4 to reciprocate the piston 7 therein, thereby selectively closing and opening the pivotable frame member 22.

In order to control the position of the slide valve piston 31 such is provided with a piston rod 38 connected to a further piston rod 39 of a control piston 40 slidable in a cylinder 41. The piston 40 is adapted to be placed under a selective spring bias by means of an adjustment member 42 which allows setting of the bias of the spring member 43 acting against this piston 40 in accordance with a desired, predetermined resistance force with which the refuse acts against the piston 7 of the cylinder 4. The other face of the spring-biased piston 40 communicates with the pressure line 11 feeding medium to the bottom face of the piston 7 of cylinder 4. Now, let it be assumed that the adjustment member 42 has set the bias of the spring 43 to a predetermined resistance force of the refuse, with the slide valve piston 31 located in its full line position shown and with pressurized fluid medium supplied via line 11 to the bottom of the cylinder 4 to drive the frame 2 into its closing position i.e., to the left of FIGURE 1. Thus, as soon as the refuse offers a resistance to the further closing movement of such frame 2, corresponding to the spring setting, then the pressure in line 11 builds-up and then shifts the piston 40 to the right end of the cylinder 41 to compress the spring 43 and, at the same time, shifts the slide valve piston 31 via the connecting rods 39, 38 into its phantom line position, whereupon fluid is now admitted to the upper face of the piston 7 via the line 12, to return the frame 2 back into its open position. When such occurs, the pressure in line 11 has sufliciently dropped so that the compressed spring 43 can again relax, moving the piston 40 again to the left and, therewith, also the slide valve piston 31 back into its full line position, with fluid under pressure moving once again through line 11 to again close the frame 2, as aforedescribed. In this manner, and aS should be evident, the pressurized fluid medium can be selectively admitted to one or the other side of the piston 7 as a function of the adjustment setting of the control means 13.

In order to ensure that the slide valve piston 31 assumes its phantom lines position for a suflicient time so that fluid is admitted to line 12 to return the piston to the lower end of the cylinder 4, there can be further provided a dash-pot arrangement 44 comprising a piston 45 having a piston rod 46 extending through the dashpot cylinder 47 and operatively connected to the control piston 40, The dash-pot cylinder 47 is advantageously filled with a fluid medium, such as oil. The piston 45 thereof is here shown as provided with a first bore or opening 48, which if desired could be made adjustable in size, and a further bore or opening 49 provided with a flap valve 50 or equivalent structure. The opening 48 allows the oil in the dash-pot cylinder 47 to move freely from one face to the other of the dash-pot piston 45, whereas the flap valve 50 only allows such oil to move from the right face of the piston 45 to the left face thereof when the piston 45 is moved toward the right end of the cylinder 47. Thus, by virtue of this arrangement, when the control piston 40 moves to the left in order to shift the slide valve piston 31 back into its full line position, the dash-pot piston 45 retards such movement of the control piston 40, since the dash-pot oil can only move from the left end of the dash-pot cylinder 47 to the right end thereof via the opening 48, so that it is ensured that the slide valve piston 31 maintains its phantom line position for a length of time sufficient to return the piston 7 to the bottom end of the cylinder 4.

The manner of operation of the heretofore described apparatus is as follows: The pivotable frame 2 is located in its open position depicted in FIGURE 1. In this position, both of the frames 1 and 2 form a receiving mouth or hopper which opens towards the top, into which a charge of refuse to be reduced in size is introduced from above. Thereafter, the piston 7 has applied to its lower face a pressurized fluid medium, such as oil, via the supply line 11, so that the piston 7 together with its piston rod 8 is moved upwardly in the cylinder 4 and, thereby, at the same time rocks the pivotable frame 2 towards the stationary frame 1. As a result, the charged material is crushed and/or compressed, depending upon its properties, whereby however, the momentary closing stroke of the frame 2 is automatically limited by the mechanical resistance of the refuse charge, since previously the adjustable or settable infeed of the pressure fluid medium and, therewith, the driving force of the piston 7 has been adjusted at the control device or means 13 to a specific resistance force acting against the piston 7, as previously explained. Thus, as soon as the increasing resistance of the material to be compressed equals the adjusted working force of the piston 7, the latter is brought to rest. Then the control device 13 immediately switches the oil infeed through the supply line 12 to the upper face of the piston 7, as explained, so that this piston 7 again moves downwardly in the cylinder 4 and, at the same time, pivots the frame 2 back into its opening position.

Consequently, the crushed and/or compressed material disposed between the two frames 1 and 2 slides downwardly. After the frame 2 has reached its open position, it will be recalled, the control device 13 again switches the oil infeed through the supply line 11 to the lower face of the piston 7, so that such piston is again upwardly displaced and the frame 2 is pivoted towards its closing position. In this manner, the material is once again acted upon, that is, is still further crushed and compressed, and indeed, with a larger efiective pressing or compression force than with the previous closing stroke, since in consequence of the dropping of the compressed material between the two frames 1 and 2 the effective lever arm with respect to the pivot axis 3' of the hinge 3 has become smaller. In this manner, due to a number of repeated opening and closing operations of the frame 2, with continuous sliding of the material, there results a continuous crushing and/or compression of such material by means of the compressive force exerted by the frame 2 which becomes increasingly effective from one closing movement to the other, as aforedescribed.

As a result, the material which is sliding down between the two frames 1 and 2 finally, however, arrives in the operating zone of the shearing means 15 and 15', so that this material which previously was only crushed and/or compressed is now, during the closing movement of the frame 2, exposed to a shearing action and thereby chopped or cut to pieces, that is, reduced in size. In the end phase of this size reduction process the resilient or spring biased shutter 16 finally moves back into the position indicated in phantom lines in FIGURE 1, so that the crushed and/or compressed, and finally size reduced material can fall through the stationary frame 1,

and is adapted to be ultimately transported by mechanical means to a combustion or incineration furnace.

With a sufiiciently small space between the stationary and the pivotable shearing means there is obtained an excellent shearing efiect, whereby the shearing means can be provided with suitable shearing or cutting edges formed of a hard material, whether such be obtained through a solid construction, reinforcement or built-up Welding of such shearing means.

The advantage of this apparatus resides in that, by the use thereof, bulky objects and objects which previously could only be reduced in size with great difficulty, as for instance chests, boxes, mattresses and so forth, can be reliably converted into easily chargeable combustible materials. Further, this apparatus can be readily accommodated to the properties or characteristics of the refuse to be size reduced, so that in this manner an effective preparation of the refuse into a combustible material can be achieved, thereby ensuring for a completely economical and positive operation of the incineration furnace, without requiring some form of manual presorting and/or size reduction. The apparatus of the present invention also has the purpose of producing refuse which is as homogeneous or uniform as possible, whereby, as a result, the subsequent destruction of such refuse by techniques other than combustion will be simplified and rendered easier to carry out.

It is, of course, to be readily understood and appreciated that various modifications of the described apparatus are possible and within the teachings of the invention. Thus, for example, the apparatus could be so constructed that both frames are arranged to rock or pivot toward one another, with each such frame being provided with a hydraulic drive device. Instead of a single cylinder it is also possible to arrange two or more cylinders at the pivotal frame or frames. Moreover, in place of a hydraulic drive arrangement, which for example works with oil as the pressure fluid, it is also possible to employ a pneumatic drive arrangement. Likewise, it would be also possible to use a purely mechanical drive, whereby the adjustability of the stroke limiter can be obtained, in known manner, through the employed electric motors. Furthermore, the pivotable or rockable frame 2 may not be articulated or pivotally connected with the stationary frame 1, but rather, its pivot axis can also he supportingly arranged next to the frame 1, preferably, however, in the region or vicinity of such frame.

While there is shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practised within the scope of the following claims.

Having thus described the present invention, what is desired to be secured by United States Letters Patent, is:

1. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of frame members, means mounting at least one of said frame members for pivotal movement, drive means for pivoting the pivotal mounted frame member towards the other frame member, shearing means provided for both of said frame members, said shearing means of each frame member incorporating spaced shearing elements providing a recess between each two neighboring shearing elements, said recess extending throughout the thickness of the corresponding frame member, said shearing elements of said shearing means of any one frame member being offset with respect to said shearing elements of the shearing means of the other frame member to permit comb-like interengagement of said shearing means of both frame members in one extreme position of said pivotal mounted frame member.

2. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, com prising a pair of cooperating and confronting frame members, means mounting at least one of said frame members for pivotal movement, drive means for pivoting the pivotal mounted frame member toward the other frame member, shearing means provided for both of said frame members at the portions of said frame members disposed adjacent to said mounting means and with the remainder of the confronting surfaces of said frame members providing the actual crushing surfaces for said refuse, said shearing means of each frame member incorporating spaced shearing elements providing a recess between each two neighboring shearing elements, said recess extending throughout the thickness of the corresponding frame member, said shearing elements of said shearing means of any one frame member being offset with respect to said shearing elements of the shearing means of the other frame member to permit comb-like interengagement of said shearing means of both frame members in one extreme position of said pivotal mounted frame member.

3. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of cooperating frame members movable into a first position for receiving refuse therebetween and into a second position for processing such refuse, means mounting at least one of said frame members for pivotal movement, drive means for pivoting the pivotal mounted frame member toward the other frame member, shearing means provided for both of said frame members at least at the lower portions of said frame members confronting one another, said shearing means of each frame member incorporating spaced shearing elements providing a recess between each two neighboring shearing elements, said recess extending throughout the thickness of the corresponding frame member, said shearing elements of said shearing means of any one frame member being offset with respect to said shearing elements of the shearing means of the other frame member to enable the shearing elements of a given frame member to move through the recesses of the other frame member, thus resulting in comb-like interengagement of said shearing means of both frame members in said second position of said frame members.

4. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of cooperating and confronting frame members mounted for relative movement toward and away from one another to assume a first position Wherein said frame members are spaced from one another to form a hopper for receipt of refuse and a second position wherein said frame members are closer to one another in order to process the refuse located between said frame members, drive means for imparting relative movement to said frame members, shearing means provided for each of said frame members, said shearing means of each frame member incorporating spaced shearing elements providing a recess between each two neighboring shearing elements, said recess extending throughout the thickness of the corresponding frame member, said shearing elements of said shearing means of any one frame member being offset with respect to said shearing elements of the shearing means of the other frame member to permit interengagement of said shearing means of both frame members in the extreme location of said second position.

5. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of cooperating and confronting frame members mounted for relative movement toward and away from one another to assume a first position wherein said frame members are spaced from one another to form a hopper including an infeed mouth for receipt of refuse and a second position wherein said frame members are closer to one another in order to process the refuse located between said frame members, drive means for imparting relative movement to said frame members, shearing means provided for each of said frame members at least at the respective ends thereof remote from said infeed mouth, said shearing means of each frame member incorporating spaced shearing elements providing a recess between each two neighboring shearing elements, said recess extending throughout the thickness of the corresponding frame member, said shearing elements of said shearing means of any one frame member being offset with respect to said shearing elements of the shearing means of the other frame member to enable intergripping of said shearing means of both frame members in the extreme location of said second position.

6. Apparatus for the size reduction of refuse according to claim 5 wherein said drive means includes means for regulating the movement of said frame members toward one another as a function of the resistance encountered by the refuse being processed.

7. Apparatus for the size reduction of refuse according to claim 6 wherein said shearing elements of each of said shearing means are defined by spaced, substantially parallel strip members, with the strip members of the shearing means of the one frame member being receivable in the respective recesses between the strip members of the shearing means of the other frame member.

8. Apparatus for the size reduction of refuse according to claim 7 wherein at least one of said frame members is mounted to be pivotal toward the other frame member, said one pivotal mounted frame member including a portion provided with said shearing means which is arched toward the shearing means of said other frame member.

9. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of cooperating frame members for receiving refuse therebetween, means mounting at least one of said frame members at one end for pivotal movement, drive means for pivoting the pivotal mounted frame member towards the other frame member, shearing means provided for both of said frame members at leastat the ends of said frame members disposed adjacent to said mounting means, said shearing means of each frame member incorporating spaced shearing elements providing a recess between each two neighboring shearing elements, said recess extending throughout the thickness of the corresponding frame member, said shearing elements of said shearing means of any one frame member being offset with respect to said shearing elements of the shearing means of the remaining frame member to enable the shearing elements of a given frame member to move through the recesses of the other frame member, thus resulting in comb-like interengagement of said shearing means of both frame members in an extreme position of said pivotal mounted frame member.

10. Apparatus for the size reduction of refuse according to claim 9 including means stationarily mounting the other of said frame members, with said one pivotal mounted frame member being pivotal toward the stationarily mounted frame member.

11. Apparatus for the size reduction of refuse according to claim 9 wherein both of said frame members in an open position of said one pivotal mounted frame member are open toward their respective upper end remote from said mounting means, said mounting means of said one pivotal mounted frame member comprising a pivot shaft, said shearing elements of said shearing means of both frame members extending approximately vertical to the aforesaid pivot shaft.

12. Apparatus for the size reduction of refuse according to claim 9 wherein said drive means are constructed to be double-acting and include control means settable to a predetermined closing force for limiting the closing stroke of said pivotal mounted frame member towards said other frame member, whereby said pivotal mounted frame member upon reaching said predetermined closing force is automatically switched-over into an opening stroke away from said other frame member due to coaction of said control means with said double-acting drive means, so that the refuse disposed between said frame members from one opening stroke to the other moves successively downwardly and under an increasingly effective compressive force is initially crushed and/ or compressed, depending upon the properties of the refuse, and finally reduced in size by said shearing means.

13, Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of cooperating coaxially mounted frame members for receiving refuse therebetween, means mounting at least one of said frame members at one end for pivotal movement, drive means for pivoting the pivotal mounted frame member towards the other frame member, shearing means provided for both of said frame members at least at the ends of said frame members disposed adjacent to said mounting means, said shearing means of any one frame member being offset with respect to the shearing means of the remaining frame member to permit comblike interengagement of said shearing means of both frame members in an extreme position of said pivotal mounted frame member.

14. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of cooperating frame members for receiving refuse therebetween, means mounting at least one of said frame members at one end for pivotal movement, drive means for pivoting the pivotal mounted frame member towards the other frame member, shearing means provided for both of said frame members at least at the ends of said frame members disposed adjacent to said mounting means, said shearing means of any one frame member being offset with respect to the shearing means of the remaining frame member to permit comb-like interengagement of said shearing means of both frame members in an extreme position of said pivotal mounted frame member, a resiliently mounted cover member provided at the external side of said other frame member in the region of said shearing means thereof to provide a down Wardly extending closure, said cover member being raised from said other frame member by said pivotal mounted frame member shortly before the latter has reached its most extreme closing position toward said other frame member, to enable dropping through of the size reduced refuse disposed between said shearing means.

15. Apparatus for the size reduction of refuse accord ing to claim 14 wherein said shearing means of said pivotal mounted frame member is curved in convex manner in the closing direction of said pivotal frame member towards said other frame member and upon piercingly extending through the shearing means of said other frame member raises said resiliently mounted cover member from the latter.

16. Apparatus for the size reduction of refuse, particularly for refuse to be destroyed by combustion, comprising a pair of cooperating frame members for receiving refuse therebetween, means mounting at least one of said frame members at one end for pivotal movement, said mounting means including a hinge connection for interconnecting both of said frame members, drive means for pivoting the pivotal mounted frame member toward the other frame member, shearing means provided for both of said frame members at least at the ends of said frame members disposed adjacent to said mounting means, said shearing means of any one frame member being offset with respect to the shearing means of the remaining frame member to permit comb-like interengagement of said shearing means of both frame members in an extreme position of said pivotal mounted frame member.

References Cited by the Examiner UNITED STATES PATENTS 1,967,240 7/1934 Guest 241-289 X 2,377,307 6/1945 Brown 241-231 2,620,629 12/1952 Gauldie 241-198 2,950,871 8/1960 Smith 241-217 2,962,959 12/1960 Sholin 241-198 X 3,140,057 7/1964 Pollitz 241-291 X ROBERT C. RIORDON, Primary Examiner. J. SPENCER OVERHOLSER, Examiner. 

1. APPARATUS FOR THE SIZE REDUCTION OF REFUSE, PARTICULARLY FOR REFUSE TO BE DESTROYED BY COMBUSTION, COMPRISING A PAIR OF FRAME MEMBERS, MEANS MOUNTING AT LEAST ONE OF SAID FRAME MEMBERS FOR PIVOTAL MOVEMENT, DRIVE MEANS FOR PIVOTING THE PIVOTAL MOUNTED FRAME MEMBER TOWARDS THE OTHER FRAME MEMBER, SHEARING MEANS PROVIDED FOR BOTH OF SAID FRAME MEMBERS, SAID SHEARING MEANS OF EACH FRAME MEMBER INCORPORATING SPACED SHEARING ELEMENTS PROVIDING A RECESS BETWEEN EACH TWO NEIGHBORING SHEARING ELEMENTS, SAID RECESS EXTENDING THROUGHOUT THE THICKNESS OF THE CORRESPONDING FRAME MEMBER, SAID SHEARING ELEMENTS OF SAID SHEARING MEANS OF ANY ONE FRAME MEMBER BEING OFFSET WITH RESPECT TO SAID SHEARING ELEMENTS OF THE SHEARING MEANS OF THE OTHER FRAME MEMBER TO PERMIT COMB-LIKE INTERENGAGEMENT OF SAID SHEARING MEANS OF BOTH FRAME MEMBERS IN ONE EXTREME POSITION OF SAID PIVOTAL MOUNTED FRAME MEMBER. 